Method of making acids.



J. L. TUFTS. METHOD 0F MAKING ACIDS.

,APPLIOATION FILED JUNB19, 190e, RBNBWED APR. z2, 1909.

2 SHEETS-SHEET 1.

J. L. TUFTS. METHOD 0F MAKING ACIDS. APPLICATION FILED JUNE 19, 190e.RENEWBD APR. z2, 1909.

Patented Aug. 10, 1909.

2 SHEETS-SHEET 2.

` To azz whoma may mem TUNiT-nn STATES;

'PATENT oneion.A

JOHN L. TUFTS, or BOSTON, MASSACHUSETTS; AssIGNOR oE-oNE-HALF To'MERRIMAC CHEMICAL COMPANY, A CORPORATION..

'METHOD or' name acme.

.n I "Specification of Letters Patent.

Application filed .Tune 19, :1906, Serial No. 322,408. Renewed 22,.1909. SerialNo. 491,669.

Be it known that I, J CHN L. T'Ur'rs, a citizen of the Umted States,residing at Boston,

in the county of Suffolk and lState of Massachusetts, have inventedCertain new and useful Improvements` in Methods of Eifecting Reactions,of which the following is a specification. f l

This invention is amethod of eecting in an economical, eiicient andcontinuous manner such reactions as preferably take place in 'tw' o ormore practical working stages, the reactlon mixture. passing during theinitial stage through a pasty, fluid -or mobile condition asdistinguished fromthelsolid condition which is attained as the. reactionpro- According to my invention the reaction is carried out inseparate'but communicating chambers correspondingl in number to thenumber of practical working stages. The

reacting bodies are preferablysupplied in a' condition hereinafterreferred to' as the pasty stage and attain the solid condi# tion; Aasthe materials become solidthey are .withdrawn from the rst chamber andtransferred to a Second chambery in which they are subjected to suchhigher temperature as the reaction'may require. The removal of the solidportions from the first Chamber is i accomplished Withoutinterferingwith the course of thereaction vorits continuous character, the pastyportions of the mixture heing permitted to remain until they in turnassume the solid condition.

As examples ef 'reactions which pass through the pasty Istageabovereferred to I may refer to the production of'hydroc'hloric acid byreaction between sodium chlorid and sulfuric acid,v and the roductio'n'of acetic acid by the decompositlon of, calcium acetate by sulfuricacid.I will describe the'y method by reference to the manufacture ofhydrochloric acid, it -bemg understood. that the invention is notrestricted thereto.

. `For a full understanding of the invention ings showing a preferredform of apparatus for carrying the same into effect;

, reference fis made to the accompanying draw- Figure 1 isl a verticallongitudinal section of a preferred formof furnace on line 1'1 of Fig..2; Fig. 2 is a plan view of the apparatus shown in Fig. l, portions ofthe bevel gear for operating the stirring mechanism being broken away;and Figs-3, 4 are-plan views of stirring arms adapted for use in theupper and lower chambers, respectively'.

Referring to the drawings, the furnace is lshown as comprisingsuperposed Chambers` 1, '2, communication lbetween which is establishedthrough a vertical flue 3.

"4 isa vertical shaft, suitably incased as indicated at 5, extendingthrough the cham- Ibers and the iue 3 and mounted in suitable upper andlower bearings 6 and 7 the upper bearing 6 being supported by okes 6%mounted on the furnace casing. A .cured to the shaft 4 above the upperchamber 1 meshes with a bevel gear 9 carried by a shaft 10 and adaptedto be driven by a worm gear 11; for clearness of illustration thecasingy of the. worm gear v11, which carries also the bearings for theshaft 10,' is removed.

I It will be understood that the shaft may be driven by a bevel gear vorequivalent `means secured to the lower portion thereof.

The charge, which may consist in one spe-v cie instance of sodiumchlorid and sulfuric acid in reacting proportions, is fed, preferablycontinuously, to the Vupper chamber ata point near the peripherythereof. In

rthe construetionshown the'salt is supplied to a hopper12, and carriedby a screw conveyer 13' to the' chamber 1, `the acid being introducedlinto the casing of said conveyer intermediate its ends through ipe 14;this arran'gementinsures a thorougi mixing of the, charge prior to itsintroduction into the furnace. An aperture lfor the escape of gaseousreaction products is provided at 15, 1n the dome of the upper reactionchamber,

and communicates with suitable condensing or collecting devices as Willbe readily understood; and a self-sealing dischar e gate 16 lis providednear the periphery o the lower chamber. 17, y18 represent normallyclosed apertures affording access to the interior of i ment therein.

.. the stirring arms, 'each chamber one l Sinto the lower chamber,

mass even when in the 40 the furnace; an ,aperture 17 gives access tv'othe chamber 2.

, -the mixture outwardl and to discharge it .through fthe peripheraopening or openings 16. It will be noted that the sockets 22 carryingthe plow blades are sodisposed in each of these arms thatthematerialldisplaced by the plows carried by one half-arm 1s movedldirectly into the path of a plow carried bythe other half-arm, therebyeffecting a positive transfer of the material in the direction aboveindicated. .The plows may beheld rigidly in the sockets vof vthe plowarms or may'havea free vertical move- In order to ling vunder anyconditions around and above d or morestationary lwipers 23, l24,preferably in the form of open frames or blades of met-al .projectingfrom .the domes of the respective chambers; these wipers are disposedimmediately above the lplpvv arms and serve as above noted to preventaccumulation thereon of the. reacting stiff and heavy paste. In order toprevent 'accumulation of material on the sides of the chambers 25,illustrated I preferably provideI Scrapers as'integral with the clampinginember of the outermost plow in each chamber. f

' vThe hearth and dome of each chamber are preferably construct'edof..cast iron, the wall ofthe l of acid.` For this reason I 'arefractoryflining,

\ character above-described that the material -ployed acting m1xtu`reand its products without 4seriousor ower chamber being indicated asinteriorly faced with refractory brick. Where a comparatively hightemperature is emca'stiron may be exposed to the rerapid corrosion,whereas at relatlvely low temperatures it is attacked with comparativerapidity owing to condensation such.' interior surfaces as-are not inimmediate proximity tothe Hues, as, for mstance,

the dome ofthe upper reacting chamber.

It is desi/fable in effecting reactions of the I should be retained. inthe upper chamber until the initial stage ofthe reaction is complete anduntil `it has reachedf a .solid as until portions of prevent the chargefrommassv I prefer to provide inA chamber l,

condition -of `a* very of heat with preferto provide as indicated at 26,fordistinguished from a pasty or mobile condition. It is furtherdesirable that the material in said upper chamber should be subjected toa relatively low temperature, and that the rate of evolution of gastherefrom should be maintained as nearly constant as is practicable inorder that the condensers may be effectively utilized. In the hearth ofthe upper chamber l I provide one or more peripheral channels ordepressions 27. into the'outer of which the fresh material isfed and inwhich it is worked by the outer plows 21, being kept by means of thesechannelsor depressions in a more or less stratified condition. Thismaterial being in the pasty or mobile condition above described is notdisplaced from the channels bythe plows, but is merely worked, stirredvor moved therein it become solid, `whereupon such portions areIdisplaced from the channel by the plows, to be discharged by Hue 3 intothe lowerchamber. Such working and transfer of the material in theinitial stage of the reaction is automatically effected, and thearrangement 'is such as t'o insure the retention of the charge in theupper chamber until it has attained" the; solid state and is adapted fortreatment at a higher tempera'- ture in the lower chamber.

In order tosecure the proper temperature conditions in the respectivechambers, I prefer to provide a combustion furnace 28, having Hues 29.30, 31 extending between the chambers and thence beneath the lowerchamber. Beneath the upper or initial and within the Hue'29, I arrangemeans forv preventing direct access of the heated Hue gases to thehearth of said initial chamber: any means which will check or. preventthe direct circulation of the heated gases in contact with this hearthwill sufce, such, for instance, as a partition extending inwardly fromthe setting of the hearth but providing an annular aperture around thesheathing of the vertical Hue .3; my preferred construction, however, isa checker- Work arch of fire-brick as indicated at 32 in Fig. l,providing a dead gas space 33 beneath the hearth of the upper chambersaid. gas space communicating through numerous apertures 32 with the Hue29. This arrangement of Hues insures a proper distribution a markedeconomy of fuel. The lower or calcining chamber 2 is subjected to a highand uniform temperature, while' the `upper chamber receives suchmoderate heatmg as the initial stage ofthe reaction, requires, and noportion of the chambers or of the furnace construction is liable tooverheating.

The apparatus herein described is claimed in my copending application,Serial Number 322,409, filed June 22, 1906.

I claim:

l. The continuous method of producing of heat.

Vof decomposingy the same, working the mixture under the influence ofheat until por.-

tions of the same become solid, continuously displacing such solidportions from the remaining pasty portions, ycontinuing the working ofsaid pasty portions and subjecting tlie displaced solid portions to theaction ofheat.

2. The continuous method of producingv hydrochloric acid which consistsin comminglin la chlorid `and an acid body capable of ecomposing thesaine, Working the mixture under theinfluenceof heat until portions ofthe same becomqe solid, continu'- ously displacing such solid vportionsfrom the remaining' pasty portions, `continiiing. the

' working of said pasty portions and subjecting the displaced solidportions to the action The continuous 4method oli-producing hydrochloricacid which consists in commingling sodium chloridand sulfuric acid,working the'mixtur'e under the iniuence of' heat until-portionsof thesame become solid, continuous y displacing such solid portions from theremaining pastyk portions, continuing the working of saidpasty portionsand -of decomposing the same, working the mix- `maining working o said(pasty portions, and subjectsuhjec'tin thedisplaced solid portions tothe 30 action o heat.

4. The continuous methodof producing hydrochloric acid which consists incommingling a chlorid and an acid body capable ture at a moderatetemperature until portions of the same become solid, continuouslydisplacing such solid portions `from the reasty portions, continuing theing the displace temperature.

A5. The. continuous method of producing solid portions to a higher-*hydrochloric acid which consists in comlmin ling sodium chlorid andsulfuric acid,

wor ing the mixturel at a moderate tempera- 'ture until vortions of thesame become solid,

continuous y displacing such solid portions from the remaining pastyportions, continuf F ing the working of said pasty portions, and

subjecting the displaced solid portions to a higher temperature.

In testimony whereof, I afli'x my signature in presenceof two witnesses.

v JOHN L. TUFTS. Witnesses:l

' ARTHUR P. CARPENTER,

.FRANCIS M. Brunn.

